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causing other unanticipated issues. The best rule of thumb is asimple one “ . do
not expect to fix mechanical problems with software!”
Use of Batch Control Software
In the last few years, new software technology has appeared on the scene in an
attempt to make the software development process simpler and more flexible for
processes with complex batch sequences. Known as batch engines, these software
packages are offered by numerous vendors and work in conjunction with the
controllers in the system, providing overall supervisory sequential controlwhile the
nuts and bolts of the control software are still handled at the controller level.
Some users have utilized this batch control software in CIP applications with
mixed results and caution should be exercised if one is considering this for their
application. Probably the biggest concern is the fact that the execution speed for
these batch engines is not always fast and repeatable. Some steps of the CIP
program may only run for afew seconds whereas some batch engines simply
cannot sequence that fast, leading to program steps that run significantly longer
than expected. Some systems with these batch engines have experienced problems
with varying CIP circuit cycle times due to differentsystem loads at various times of
the day. Remember that the proper control oftime is one of the most basic CIP
requirements and the batch engine needs to be able to keep up with the process!
Designing Software for Maintenance and Troubleshooting
Much attention has been paid in the last few years to developing software for CIP
applications that does aproper job of ensuring that the CIP process is tightly
controlled such that the cleaning effectiveness is maintained consistently, day after
day. Asaresult, newer systems are now equipped with many more critical alarms
then their predecessors. These alarms are usually programmed to abort the CIP
process if problems are encountered.
One thing that is often overlooked; however, is the fact that these alarms can
become areal nuisance during commissioning or when troubleshooting aproblem.
Thealarm itself is notthe problem, butthe resultantaborted sequence canbe. It is often
desirable to continue on with the sequence tomakeobservationsofthe root cause of
an alarm when commissioning and troubleshooting. Itisrecommended that provisionsbemadetobeabletoignorethese
abortconditionsifdesired. (Ofcourse, certain
abort conditions must not be disabled such that personnel safety iscompromised or
equipmentispossiblydamaged.) Also,the appropriatesecurityprovisionswillneed
to be in placesothatthisfunctionality cannot be used inappropriately.
CIP QUALITY CONTROL TOOLS
Alarm Functions
Today’s modern control systems allow easy development of alarms to monitor and
cause appropriate action for the required critical process parameters related to CIP
operations. Obviously,alarm monitoring of flow,conductivity,and temperature are
critical to this process, but most systems have alarm functions for many other
process parameters as well. The various system alarms and desired actions need to
be determined on acase by case basis for each application. The user will most
certainly have asubstantial interest in the development of these system requirements
so that CIP performance is closely monitored and controlled to help ensure
quality control during cleaning operations.